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%I #16 Aug 26 2025 08:47:44
%S 15,24,34,54,72,76,88,102,110,131,153,162,173,189,255,324,342,353,374,
%T 545,705,721,736,741,747,756,765,838,922,939,947,960,969,977,987,1000,
%U 1015,1026,1032,1047,1065,1080,1094,1100,1106,1130,1152,1167,1187
%N Interemirp sequence: average of emirp pairs, analogous to interprimes.
%H Michael De Vlieger, <a href="/A079721/b079721.txt">Table of n, a(n) for n = 1..10000</a>
%H Michael Joseph Halm, <a href="http://untilheaven.tripod.com/id112.htm">Sequences</a>
%F a(n) = (A006567(n) + A006567(n+1))/2 where A006567(n) is the n-th emirp.
%e a(1) = 15 because the first two emirps are 13 and 17 and (13 + 17)/2 = 15
%t Map[Apply[Total, {##}]/2 &, Partition[Select[Prime[Range[5, 196]], And[PrimeQ@ IntegerReverse[#], ! PalindromeQ[#] ] &], 2, 1]] (* _Michael De Vlieger_, Aug 26 2025 *)
%Y Cf. A006567, A024675.
%K nonn,base
%O 1,1
%A _Michael Joseph Halm_, Feb 17 2003
%E a(4) corrected by _Sean A. Irvine_, Aug 25 2025